package org.bouncycastle.jce.provider;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.math.BigInteger;
import java.security.interfaces.ECPrivateKey;
import java.security.spec.ECParameterSpec;
import java.security.spec.ECPoint;
import java.security.spec.ECPrivateKeySpec;
import java.security.spec.EllipticCurve;
import java.util.Enumeration;

import org.bouncycastle.asn1.ASN1Object;
import org.bouncycastle.asn1.ASN1Sequence;
import org.bouncycastle.asn1.DERBitString;
import org.bouncycastle.asn1.DEREncodable;
import org.bouncycastle.asn1.DERInteger;
import org.bouncycastle.asn1.DERNull;
import org.bouncycastle.asn1.DERObject;
import org.bouncycastle.asn1.DERObjectIdentifier;
import org.bouncycastle.asn1.pkcs.PrivateKeyInfo;
import org.bouncycastle.asn1.sec.ECPrivateKeyStructure;
import org.bouncycastle.asn1.x509.AlgorithmIdentifier;
import org.bouncycastle.asn1.x509.SubjectPublicKeyInfo;
import org.bouncycastle.asn1.x9.X962Parameters;
import org.bouncycastle.asn1.x9.X9ECParameters;
import org.bouncycastle.asn1.x9.X9ObjectIdentifiers;
import org.bouncycastle.crypto.params.ECDomainParameters;
import org.bouncycastle.crypto.params.ECPrivateKeyParameters;
import org.bouncycastle.jce.interfaces.ECPointEncoder;
import org.bouncycastle.jce.interfaces.PKCS12BagAttributeCarrier;
import org.bouncycastle.jce.provider.asymmetric.ec.EC5Util;
import org.bouncycastle.jce.provider.asymmetric.ec.ECUtil;
import org.bouncycastle.jce.spec.ECNamedCurveSpec;
import org.bouncycastle.math.ec.ECCurve;

public class JCEECPrivateKey implements ECPrivateKey,
        org.bouncycastle.jce.interfaces.ECPrivateKey,
        PKCS12BagAttributeCarrier, ECPointEncoder {
    private static final long serialVersionUID = 1160666905419364165L;
    private String algorithm = "EC";
    private BigInteger d;
    private ECParameterSpec ecSpec;
    private boolean withCompression;

    private DERBitString publicKey;

    private PKCS12BagAttributeCarrierImpl attrCarrier = new PKCS12BagAttributeCarrierImpl();

    protected JCEECPrivateKey() {
    }

    public JCEECPrivateKey(ECPrivateKey key) {
        this.d = key.getS();
        this.algorithm = key.getAlgorithm();
        this.ecSpec = key.getParams();
    }

    public JCEECPrivateKey(String algorithm,
            org.bouncycastle.jce.spec.ECPrivateKeySpec spec) {
        this.algorithm = algorithm;
        this.d = spec.getD();

        if (spec.getParams() != null) // can be null if implicitlyCA
        {
            ECCurve curve = spec.getParams().getCurve();
            EllipticCurve ellipticCurve;

            ellipticCurve = EC5Util.convertCurve(curve, spec.getParams()
                    .getSeed());

            this.ecSpec = EC5Util.convertSpec(ellipticCurve, spec.getParams());
        } else {
            this.ecSpec = null;
        }
    }

    public JCEECPrivateKey(String algorithm, ECPrivateKeySpec spec) {
        this.algorithm = algorithm;
        this.d = spec.getS();
        this.ecSpec = spec.getParams();
    }

    public JCEECPrivateKey(String algorithm, JCEECPrivateKey key) {
        this.algorithm = algorithm;
        this.d = key.d;
        this.ecSpec = key.ecSpec;
        this.withCompression = key.withCompression;
        this.attrCarrier = key.attrCarrier;
        this.publicKey = key.publicKey;
    }

    public JCEECPrivateKey(String algorithm, ECPrivateKeyParameters params,
            JCEECPublicKey pubKey, ECParameterSpec spec) {
        ECDomainParameters dp = params.getParameters();

        this.algorithm = algorithm;
        this.d = params.getD();

        if (spec == null) {
            EllipticCurve ellipticCurve = EC5Util.convertCurve(dp.getCurve(),
                    dp.getSeed());

            this.ecSpec = new ECParameterSpec(ellipticCurve, new ECPoint(dp
                    .getG().getX().toBigInteger(), dp.getG().getY()
                    .toBigInteger()), dp.getN(), dp.getH().intValue());
        } else {
            this.ecSpec = spec;
        }

        publicKey = getPublicKeyDetails(pubKey);
    }

    public JCEECPrivateKey(String algorithm, ECPrivateKeyParameters params,
            JCEECPublicKey pubKey,
            org.bouncycastle.jce.spec.ECParameterSpec spec) {
        ECDomainParameters dp = params.getParameters();

        this.algorithm = algorithm;
        this.d = params.getD();

        if (spec == null) {
            EllipticCurve ellipticCurve = EC5Util.convertCurve(dp.getCurve(),
                    dp.getSeed());

            this.ecSpec = new ECParameterSpec(ellipticCurve, new ECPoint(dp
                    .getG().getX().toBigInteger(), dp.getG().getY()
                    .toBigInteger()), dp.getN(), dp.getH().intValue());
        } else {
            EllipticCurve ellipticCurve = EC5Util.convertCurve(spec.getCurve(),
                    spec.getSeed());

            this.ecSpec = new ECParameterSpec(ellipticCurve, new ECPoint(spec
                    .getG().getX().toBigInteger(), spec.getG().getY()
                    .toBigInteger()), spec.getN(), spec.getH().intValue());
        }

        publicKey = getPublicKeyDetails(pubKey);
    }

    public JCEECPrivateKey(String algorithm, ECPrivateKeyParameters params) {
        this.algorithm = algorithm;
        this.d = params.getD();
        this.ecSpec = null;
    }

    JCEECPrivateKey(PrivateKeyInfo info) {
        populateFromPrivKeyInfo(info);
    }

    private void populateFromPrivKeyInfo(PrivateKeyInfo info) {
        X962Parameters params = new X962Parameters((DERObject) info
                .getAlgorithmId().getParameters());

        if (params.isNamedCurve()) {
            DERObjectIdentifier oid = (DERObjectIdentifier) params
                    .getParameters();
            X9ECParameters ecP = ECUtil.getNamedCurveByOid(oid);

            // BEGIN android-removed
            // if (ecP == null) // GOST Curve
            // {
            // ECDomainParameters gParam = ECGOST3410NamedCurves.getByOID(oid);
            // EllipticCurve ellipticCurve =
            // EC5Util.convertCurve(gParam.getCurve(), gParam.getSeed());
            //
            // ecSpec = new ECNamedCurveSpec(
            // ECGOST3410NamedCurves.getName(oid),
            // ellipticCurve,
            // new ECPoint(
            // gParam.getG().getX().toBigInteger(),
            // gParam.getG().getY().toBigInteger()),
            // gParam.getN(),
            // gParam.getH());
            // }
            // else
            // END android-removed
            {
                EllipticCurve ellipticCurve = EC5Util.convertCurve(
                        ecP.getCurve(), ecP.getSeed());

                ecSpec = new ECNamedCurveSpec(ECUtil.getCurveName(oid),
                        ellipticCurve, new ECPoint(ecP.getG().getX()
                                .toBigInteger(), ecP.getG().getY()
                                .toBigInteger()), ecP.getN(), ecP.getH());
            }
        } else if (params.isImplicitlyCA()) {
            ecSpec = null;
        } else {
            X9ECParameters ecP = new X9ECParameters(
                    (ASN1Sequence) params.getParameters());
            EllipticCurve ellipticCurve = EC5Util.convertCurve(ecP.getCurve(),
                    ecP.getSeed());

            this.ecSpec = new ECParameterSpec(ellipticCurve, new ECPoint(ecP
                    .getG().getX().toBigInteger(), ecP.getG().getY()
                    .toBigInteger()), ecP.getN(), ecP.getH().intValue());
        }

        if (info.getPrivateKey() instanceof DERInteger) {
            DERInteger derD = (DERInteger) info.getPrivateKey();

            this.d = derD.getValue();
        } else {
            ECPrivateKeyStructure ec = new ECPrivateKeyStructure(
                    (ASN1Sequence) info.getPrivateKey());

            this.d = ec.getKey();
            this.publicKey = ec.getPublicKey();
        }
    }

    public String getAlgorithm() {
        return algorithm;
    }

    /**
     * return the encoding format we produce in getEncoded().
     * 
     * @return the string "PKCS#8"
     */
    public String getFormat() {
        return "PKCS#8";
    }

    /**
     * Return a PKCS8 representation of the key. The sequence returned
     * represents a full PrivateKeyInfo object.
     * 
     * @return a PKCS8 representation of the key.
     */
    public byte[] getEncoded() {
        X962Parameters params;

        if (ecSpec instanceof ECNamedCurveSpec) {
            DERObjectIdentifier curveOid = ECUtil
                    .getNamedCurveOid(((ECNamedCurveSpec) ecSpec).getName());
            if (curveOid == null) // guess it's the OID
            {
                curveOid = new DERObjectIdentifier(
                        ((ECNamedCurveSpec) ecSpec).getName());
            }
            params = new X962Parameters(curveOid);
        } else if (ecSpec == null) {
            params = new X962Parameters(DERNull.INSTANCE);
        } else {
            ECCurve curve = EC5Util.convertCurve(ecSpec.getCurve());

            X9ECParameters ecP = new X9ECParameters(curve,
                    EC5Util.convertPoint(curve, ecSpec.getGenerator(),
                            withCompression), ecSpec.getOrder(),
                    BigInteger.valueOf(ecSpec.getCofactor()), ecSpec.getCurve()
                            .getSeed());

            params = new X962Parameters(ecP);
        }

        PrivateKeyInfo info;
        ECPrivateKeyStructure keyStructure;

        if (publicKey != null) {
            keyStructure = new ECPrivateKeyStructure(this.getS(), publicKey,
                    params);
        } else {
            keyStructure = new ECPrivateKeyStructure(this.getS(), params);
        }

        // BEGIN android-removed
        // if (algorithm.equals("ECGOST3410"))
        // {
        // info = new PrivateKeyInfo(new
        // AlgorithmIdentifier(CryptoProObjectIdentifiers.gostR3410_2001,
        // params.getDERObject()), keyStructure.getDERObject());
        // }
        // else
        // END android-removed
        {

            info = new PrivateKeyInfo(new AlgorithmIdentifier(
                    X9ObjectIdentifiers.id_ecPublicKey, params.getDERObject()),
                    keyStructure.getDERObject());
        }

        return info.getDEREncoded();
    }

    public ECParameterSpec getParams() {
        return ecSpec;
    }

    public org.bouncycastle.jce.spec.ECParameterSpec getParameters() {
        if (ecSpec == null) {
            return null;
        }

        return EC5Util.convertSpec(ecSpec, withCompression);
    }

    org.bouncycastle.jce.spec.ECParameterSpec engineGetSpec() {
        if (ecSpec != null) {
            return EC5Util.convertSpec(ecSpec, withCompression);
        }

        return ProviderUtil.getEcImplicitlyCa();
    }

    public BigInteger getS() {
        return d;
    }

    public BigInteger getD() {
        return d;
    }

    public void setBagAttribute(DERObjectIdentifier oid, DEREncodable attribute) {
        attrCarrier.setBagAttribute(oid, attribute);
    }

    public DEREncodable getBagAttribute(DERObjectIdentifier oid) {
        return attrCarrier.getBagAttribute(oid);
    }

    @SuppressWarnings({ "rawtypes" })
    public Enumeration getBagAttributeKeys() {
        return attrCarrier.getBagAttributeKeys();
    }

    public void setPointFormat(String style) {
        withCompression = !("UNCOMPRESSED".equalsIgnoreCase(style));
    }

    public boolean equals(Object o) {
        if (!(o instanceof JCEECPrivateKey)) {
            return false;
        }

        JCEECPrivateKey other = (JCEECPrivateKey) o;

        return getD().equals(other.getD())
                && (engineGetSpec().equals(other.engineGetSpec()));
    }

    public int hashCode() {
        return getD().hashCode() ^ engineGetSpec().hashCode();
    }

    public String toString() {
        StringBuffer buf = new StringBuffer();
        String nl = System.getProperty("line.separator");

        buf.append("EC Private Key").append(nl);
        buf.append("             S: ").append(this.d.toString(16)).append(nl);

        return buf.toString();

    }

    private DERBitString getPublicKeyDetails(JCEECPublicKey pub) {
        try {
            SubjectPublicKeyInfo info = SubjectPublicKeyInfo
                    .getInstance(ASN1Object.fromByteArray(pub.getEncoded()));

            return info.getPublicKeyData();
        } catch (IOException e) { // should never happen
            return null;
        }
    }

    private void readObject(ObjectInputStream in) throws IOException,
            ClassNotFoundException {
        byte[] enc = (byte[]) in.readObject();

        populateFromPrivKeyInfo(PrivateKeyInfo.getInstance(ASN1Object
                .fromByteArray(enc)));

        this.algorithm = (String) in.readObject();
        this.withCompression = in.readBoolean();
        this.attrCarrier = new PKCS12BagAttributeCarrierImpl();

        attrCarrier.readObject(in);
    }

    private void writeObject(ObjectOutputStream out) throws IOException {
        out.writeObject(this.getEncoded());
        out.writeObject(algorithm);
        out.writeBoolean(withCompression);

        attrCarrier.writeObject(out);
    }
}
